The proposed research will continue a multidisciplinary prospective study of the effects of outdoor and indoor air pollutants on pulmonary function and respiratory disease during childhood and adult life. Enrollment of 13,853 children and 8,859 adults began in six eastern and midwestern cities between 1974 and 1977, accompanied by an extensive air quality monitoring program of both outdoor and indoor environments. The children have been seen annually and the adults every three years. The data are currently complete through the 1980-81 examination. The proposed research will include continued analysis of data collected prior to 1 July 1983: a) In children, to describe the development of pulmonary function and age-specific respiratory illness rates between 6 and 13 years of age and the effects of air pollution on these changes. b) In adults, to describe the effects of air pollutants on changes over 6 years in pulmonary function and respiratory morbidity. c) To relate the mortality of adults during 6-year follow-up to baseline pulmonary function, respiratory morbidity, and air pollution exposures. d) In adults and children, to relate short-term changes in pulmonary function to daily fluctuations in air quality. e) To analyze data collected from indoor and outdoor monitoring and personal exposure studies to develop indices of personal exposure to air pollutants that will refine our health effects analyses. Annual examinations of participating children will be continued until high school graduation or age 18 to investigate the development of pulmonary function through adolescence and the effects of previous exposure to air pollutants and the onset of cigarette smoking on that development. An additional cohort of third- and fourth-grade children will be enrolled in each city to investigate the health significance of changes in air quality in participating cities since the start of the study. Participating adults will be followed for current address and vital status. Air pollution monitoring will continue at a central site in each city. To develop better estimates of personal exposure, the indoor environments of 200 homes in each community will be studied. More detailed analyses and characterization of the aerosols in each city are projected.